Luminous display devices are widely used for decorative or attention-getting purposes. The most common are probably those which are made up of simple or complex lengths of tubing filled with an inert gas such as neon, argon, mercury vapor, or mixtures thereof. Also rather common are flat display devices which may serve as lighted signs having at least one transparent surface which may be masked to create letters, figures, or characters. Generally, these include two flat plates which are spaced from each other to form a chamber which is evacuated and then filled with the desired inert gas. Electrodes are arranged in such a manner as to set up a discharge path or paths in the chamber, and voltage is applied to cause ionization of the gas to produce a color display. This invention is concerned with luminous display devices of the flat plate type, but having a movable pattern of light display.
The primary object of the present invention is the improvement of performance, structural strength, and durability of flat luminous display devices.
Another object is a flat plate luminous display device operational from a simple power supply of radio-frequency voltage to produce attractive light patterns.
A further object of the present invention is the incorporation of elements between the plates of a luminous display device which facilitate its manufacture and set up various paths for gas discharge.